Reputation: 79
I am currently trying to make a stereo visual odometry using Matlab with the KITTI dataset
I know the folder 'poses.txt' contains the ground truth poses (trajectory) for the first 11 sequences. Each file xx.txt contains an N x 12 table, where N is the number of frames of this sequence. But, what are these 12 parameters? x,y,z, row, pitch, yaw and what?
My second question is if I want to create my own dataset, how can I acquire these poses with IMU?
Upvotes: 5
Views: 6844
Reputation: 506
The 12 elements are flattened 3x4 matrix of which 3x3 are for rotation and 3x1 are for translation.
You can convert these into other representations like euler(roll, pitch, yaw), quaternion.
Upvotes: 1
Reputation: 502
Each row of the file contains the first 3 rows of a 4x4 homogeneous pose matrix flattened into one line.
It means that this matrix:
r11 r12 r13 tx
r21 r22 r23 ty
r31 r32 r33 tz
0 0 0 1
is represented in the file as a single row:
r11 r12 r13 tx r21 r22 r23 ty r31 r32 r33 tz
Search "4x4 homogeneous pose matrix" in Google or read this:
http://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/MARBLE/high/pose/express.htm
or this
https://math.stackexchange.com/questions/82602/how-to-find-camera-position-and-rotation-from-a-4x4-matrix
Upvotes: 7